feat: Support configuring workspace deployment strategy in DWOC

This commit adds a new DWOC field `config.workspace.deploymentStrategy` which allows for specifying the workspace deployment strategy in the DWOC. The possible choices are `Recreate` (Default) and `RollingUpdate`. Fix devfile#1045 Signed-off-by: Andrew Obuchowicz <[email protected]>
AObuchow · Mar 29, 2023 · 78d4be3 · 78d4be3
1 parent 4f8fe70
commit 78d4be3
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Showing 6 changed files with 49 additions and 5 deletions.
diff --git a/apis/controller/v1alpha1/devworkspaceoperatorconfig_types.go b/apis/controller/v1alpha1/devworkspaceoperatorconfig_types.go
@@ -17,6 +17,7 @@ package v1alpha1
 
 import (
 	dw "github.com/devfile/api/v2/pkg/apis/workspaces/v1alpha2"
+	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -100,6 +101,14 @@ type WorkspaceConfig struct {
 	// not specified, the default value of "Always" is used.
 	// +kubebuilder:validation:Enum=IfNotPresent;Always;Never
 	ImagePullPolicy string `json:"imagePullPolicy,omitempty"`
+	// DeploymentStrategy defines the deployment strategy to use to replace existing DevWorkspace pods
+	// with new ones. The available deployment stragies are "Recreate" and "RollingUpdate".
+	// With the "Recreate" deployment strategy, the existing workspace pod is killed before the new one is created.
+	// With the "RollingUpdate" deployment strategy, a new workspace pod is created and the existing workspace pod is deleted
+	// only when the new workspace pod is in a ready state.
+	// If not specified, the default "Recreate" deployment strategy is used.
+	// +kubebuilder:validation:Enum=Recreate;RollingUpdate
+	DeploymentStrategy appsv1.DeploymentStrategyType `json:"deploymentStrategy,omitempty"`
 	// PVCName defines the name used for the persistent volume claim created
 	// to support workspace storage when the 'common' storage class is used.
 	// If not specified, the default value of `claim-devworkspace` is used.

diff --git a/pkg/config/defaults.go b/pkg/config/defaults.go
@@ -20,6 +20,7 @@ import (
 
 	"github.com/devfile/devworkspace-operator/apis/controller/v1alpha1"
 	"github.com/devfile/devworkspace-operator/pkg/infrastructure"
+	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/utils/pointer"
@@ -32,8 +33,9 @@ var defaultConfig = &v1alpha1.OperatorConfiguration{
 		ClusterHostSuffix:   "", // is auto discovered when running on OpenShift. Must be defined by CR on Kubernetes.
 	},
 	Workspace: &v1alpha1.WorkspaceConfig{
-		ImagePullPolicy: "Always",
-		PVCName:         "claim-devworkspace",
+		ImagePullPolicy:    "Always",
+		DeploymentStrategy: appsv1.RecreateDeploymentStrategyType,
+		PVCName:            "claim-devworkspace",
 		ServiceAccount: &v1alpha1.ServiceAccountConfig{
 			DisableCreation: pointer.Bool(false),
 		},

diff --git a/pkg/config/sync.go b/pkg/config/sync.go
@@ -290,6 +290,9 @@ func mergeConfig(from, to *controller.OperatorConfiguration) {
 		if from.Workspace.ImagePullPolicy != "" {
 			to.Workspace.ImagePullPolicy = from.Workspace.ImagePullPolicy
 		}
+		if from.Workspace.DeploymentStrategy != "" {
+			to.Workspace.DeploymentStrategy = from.Workspace.DeploymentStrategy
+		}
 		if from.Workspace.IdleTimeout != "" {
 			to.Workspace.IdleTimeout = from.Workspace.IdleTimeout
 		}
@@ -399,6 +402,9 @@ func GetCurrentConfigString(currConfig *controller.OperatorConfiguration) string
 		if workspace.ImagePullPolicy != defaultConfig.Workspace.ImagePullPolicy {
 			config = append(config, fmt.Sprintf("workspace.imagePullPolicy=%s", workspace.ImagePullPolicy))
 		}
+		if workspace.DeploymentStrategy != defaultConfig.Workspace.DeploymentStrategy {
+			config = append(config, fmt.Sprintf("workspace.deploymentStrategy=%s", workspace.DeploymentStrategy))
+		}
 		if workspace.PVCName != defaultConfig.Workspace.PVCName {
 			config = append(config, fmt.Sprintf("workspace.pvcName=%s", workspace.PVCName))
 		}

diff --git a/pkg/config/sync_test.go b/pkg/config/sync_test.go
@@ -26,6 +26,7 @@ import (
 	fuzz "github.com/google/gofuzz"
 	routev1 "github.com/openshift/api/route/v1"
 	"github.com/stretchr/testify/assert"
+	appsv1 "k8s.io/api/apps/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -97,6 +98,15 @@ func TestMergesAllFieldsFromClusterConfig(t *testing.T) {
 		func(_ *dw.DevWorkspaceTemplateSpecContent, c fuzz.Continue) {},
 		// Ensure no empty strings are generated as they cause default values to be used
 		func(s *string, c fuzz.Continue) { *s = "a" + c.RandString() },
+		// The only valid deployment strategies are Recreate and RollingUpdate
+		func(deploymentStrategy *appsv1.DeploymentStrategyType, c fuzz.Continue) {
+			switch c.Int() % 2 {
+			case 0:
+				*deploymentStrategy = appsv1.RollingUpdateDeploymentStrategyType
+			default:
+				*deploymentStrategy = appsv1.RecreateDeploymentStrategyType
+			}
+		},
 	)
 	for i := 0; i < 100; i++ {
 		fuzzedConfig := &v1alpha1.OperatorConfiguration{}

diff --git a/pkg/constants/constants.go b/pkg/constants/constants.go
@@ -16,6 +16,8 @@
 // Package constants defines constant values used throughout the DevWorkspace Operator
 package constants
 
+import "k8s.io/apimachinery/pkg/util/intstr"
+
 // Labels which should be used for controller related objects
 var ControllerAppLabels = func() map[string]string {
 	return map[string]string{
@@ -24,6 +26,13 @@ var ControllerAppLabels = func() map[string]string {
 	}
 }
 
+var (
+	// Maximum number of unavailable workspace pods when using the RollingUpdate deployment strategy
+	RollingUpdateMaxUnavailable = intstr.FromInt(0)
+	// Maximum number of excesss workspace pods when using the RollingUpdate deployment strategy
+	RollingUpdateMaximumSurge = intstr.FromInt(1)
+)
+
 // Internal constants
 const (
 	DefaultProjectsSourcesRoot = "/projects"

diff --git a/pkg/provision/workspace/deployment.go b/pkg/provision/workspace/deployment.go
@@ -199,6 +199,16 @@ func getSpecDeployment(
 		return nil, err
 	}
 
+	deploymentStrategy := appsv1.DeploymentStrategy{
+		Type: workspace.Config.Workspace.DeploymentStrategy,
+	}
+	if workspace.Config.Workspace.DeploymentStrategy == appsv1.RollingUpdateDeploymentStrategyType {
+		deploymentStrategy.RollingUpdate = &appsv1.RollingUpdateDeployment{
+			MaxUnavailable: &constants.RollingUpdateMaxUnavailable,
+			MaxSurge:       &constants.RollingUpdateMaximumSurge,
+		}
+	}
+
 	deployment := &appsv1.Deployment{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:        common.DeploymentName(workspace.Status.DevWorkspaceId),
@@ -213,9 +223,7 @@ func getSpecDeployment(
 					constants.DevWorkspaceIDLabel: workspace.Status.DevWorkspaceId,
 				},
 			},
-			Strategy: appsv1.DeploymentStrategy{
-				Type: appsv1.RecreateDeploymentStrategyType,
-			},
+			Strategy: deploymentStrategy,
 			Template: corev1.PodTemplateSpec{
 				ObjectMeta: metav1.ObjectMeta{
 					Name:      workspace.Status.DevWorkspaceId,